CVE-2026-54355
Severity not reportedMapServer is a system for developing web-based GIS applications.
MapServer is a system for developing web-based GIS applications. From 6.0 until 8.6.4, MapServer's OpenLayers HTML output for SERVICE=WMS&REQUEST=GetMap&FORMAT=application/openlayers reflects an attacker-controlled X-Forwarded-Host value received as HTTP_X_FORWARDED_HOST through msBuildOnlineResource(), processLine(), and the [mapserv_onlineresource] substitution in src/maputil.c and src/maptemplate.c without escaping it for a single-quoted JavaScript string. When the deployment trusts the forwarded header and does not configure a fixed ows_onlineresource or MS_ONLINERESOURCE value, embedded single quotes can escape the generated URL string. An unauthenticated attacker can craft a URL that executes arbitrary JavaScript in the MapServer site origin when opened by a victim, enabling access to sessions or tokens, same-origin data and requests, and actions as the victim. This issue is fixed in version 8.6.4.
Affected products
Not reported by the source (unknown — not "none").
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
No vendor advisory or patch reference tagged by NVD. Check the references below.
References
- https://github.com/MapServer/MapServer/commit/edc1033c7963fcffd160d85cf430f49aaf4a1374 security-advisories@github.com
- https://github.com/MapServer/MapServer/commit/ff17ef190caaeaa9002ac3d1c7969ec5315c345e security-advisories@github.com
- https://github.com/MapServer/MapServer/pull/7517 security-advisories@github.com
- https://github.com/MapServer/MapServer/pull/7518 security-advisories@github.com
- https://github.com/MapServer/MapServer/releases/tag/rel-8-6-4 security-advisories@github.com
- https://github.com/MapServer/MapServer/security/advisories/GHSA-xqj6-vjqr-33vv security-advisories@github.com
- https://mapserver.org/development/changelog/changelog-8-6.html#changelog-8-6 security-advisories@github.com
- https://github.com/MapServer/MapServer/security/advisories/GHSA-xqj6-vjqr-33vv 134c704f-9b21-4f2e-91b3-4a467353bcc0